This invention relates to strand winders and in particular to a strand accumulator which accumulates a moving strand material.
In the manufacturing and processing of strand material, such as steel wire, textile yarn, rope or fiber optic cable for example, a portion of the manufacturing or processing line may often stop or slow relative to the remainder of the line, due to strand breaks, winding reel changes or the necessity of parts replacement in certain production machines. For example, a fiber optic cable is processed through drawing devices, testing machinery and finally to a winding device for winding the fiber optic cable on a bobbin or spool. Periodically, the spool must be replaced with an empty spool and replacement can take less than a minute. It is not feasible, however, to stop the entire processing line in order to change a winding reel spool. Therefore, it is common practice to provide an accumulator between the winding reel and an adjacent processing station so that while the spool is being changed, processed strand is fed onto the accumulator. When the spool change is complete, the accumulated strand is withdrawn from the accumulator and wound onto the spool.
Heretofore, most prior art strand accumulators have required a very large space, typically extending vertically several stories high to serve as a type of looping pit for the strand material. Some improvements have been made so as to lessen the vertical height an accumulator extends. An example is U.S. Pat. No. 4,641,794 to Yamazaki, which discloses a wire accumulator where a revolving arm distributes strand material on concentric grooves formed on two sets of circularly arranged rolls. Strand tension and speed is controlled by an appropriate apparatus located on the revolving arm.
Although devices such as disclosed in Yamazaki provide an accumulator which is a more compact unit with less vertical height than many other prior art devices, the rotating arm carrying a tension and speed control apparatus is complex and creates mechanical difficulties in operation.
It is accordingly an object of the present invention to provide a strand accumulator having a compact size requiring a low vertical height as well as a minimum amount of floor space coverage.
Another object of the present invention is to provide a strand accumulator having a strand tension control apparatus which is simple and efficient in operation.